Natural Scrolling + Left Handed Mouse Buttons

Things described below are done on my Gentoo Linux on 2015-08-15. However they should apply any X11 Systems such as Debian, Ubuntu, or Arch Linux as well, because none of them are depending on Gentoo specific tools.

Problem: Natural scrolling

This should be easy. Both xfce4 and gnome have config to reverse scroll direction. However, they don’t always reverse only on some GUI apps (such as evince pdf viewer)

xmodmap seems to solve this issue, but it does not.

xmodmap has another issue that if you unplug/plug USB mouse you have to apply xmodmap again.

Let’s find a solution which doesn’t depend on xmodmap, and which also works for any apps including evince.